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lassign(n)                   Tcl Built-In Commands                  lassign(n)

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NAME
       lassign - Assign list elements to variables

SYNOPSIS
       lassign list ?varName ...?
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DESCRIPTION
       This command treats the value list as a list and assigns successive
       elements from that list to the variables given by the varName arguments
       in order.  If there are more variable names than list elements, the
       remaining variables are set to the empty string.  If there are more
       list elements than variables, a list of unassigned elements is
       returned.

EXAMPLES
       An illustration of how multiple assignment works, and what happens when
       there are either too few or too many elements.

              lassign {a b c} x y z       ;# Empty return
              puts $x                     ;# Prints "a"
              puts $y                     ;# Prints "b"
              puts $z                     ;# Prints "c"

              lassign {d e} x y z         ;# Empty return
              puts $x                     ;# Prints "d"
              puts $y                     ;# Prints "e"
              puts $z                     ;# Prints ""

              lassign {f g h i} x y       ;# Returns "h i"
              puts $x                     ;# Prints "f"
              puts $y                     ;# Prints "g"

       The lassign command has other uses.  It can be used to create the
       analogue of the "shift" command in many shell languages like this:

              set ::argv [lassign $::argv argumentToReadOff]

SEE ALSO
       lindex(n), list(n), lrange(n), lset(n), set(n)

KEYWORDS
       assign, element, list, multiple, set, variable

Tcl                                   8.5                           lassign(n)